For example, a vehicular head-up display (HUD) has been known as a display device for displaying an image (for example, see PTL 1). What is called augmented reality (AR) is used in the head-up display, and a virtual image of an image, which is formed on a movable screen, is displayed in a space in front of a windshield of a vehicle. With this configuration, a driver can view information about driving (for example, car navigation information) superimposed on a scene in front of the windshield.